Aggiunge IMAP bounce e flag email non valide nel CRM.

Permette di leggere i bounce dalla stessa MailIdentity SMTP, aggiornare le email in anagrafica e saltare gli indirizzi invalidi nei mailing.

Co-authored-by: Cursor <cursoragent@cursor.com>

test/services/mailings/imap_bounce_reader_test.rb

@@ -0,0 +1,40 @@
+require "test_helper"
+
+class Mailings::ImapBounceReaderTest < ActiveSupport::TestCase
+  test "parses aruba-style delivery failure from raw rfc822" do
+    identity = create_mail_identity(
+      from_email: "info@matchlivetv.it",
+      smtp_username: "info@matchlivetv.it",
+      smtp_host: "smtps.aruba.it",
+      smtp_port: 465,
+      encryption: "tls"
+    )
+
+    raw = <<~EML
+      From: mail-daemon@example.com
+      To: info@matchlivetv.it
+      Subject: Recapito fallito
+      Date: Mon, 07 Sep 2026 08:14:05 +0200
+      MIME-Version: 1.0
+      Content-Type: text/plain; charset=UTF-8
+
+      Delivery to the following recipients failed permanently:
+
+         * broken@club.it
+
+      Reason: 550 5.1.1 User unknown
+
+      Final-Recipient: rfc822; broken@club.it
+      Diagnostic-Code: smtp; 550 5.1.1 User unknown
+
+      Subject: Più visibilità per ASD Test Club
+    EML
+
+    reader = Mailings::ImapBounceReader.new(identity)
+    parsed = reader.send(:parse_message, raw, uid: 42)
+    assert_not_nil parsed
+    assert_includes parsed[:failed_emails], "broken@club.it"
+    assert_equal "ASD Test Club", parsed[:club_hint]
+    assert_match(/550|User unknown/i, parsed[:reason].to_s)
+  end
+end